While auditing TCP stack for upcoming 'lockless' listener changes,
I found I had to change fastopen_init_queue() to properly init the object
before publishing it.

Otherwise an other cpu could try to lock the spinlock before it gets
properly initialized.

Instead of adding appropriate barriers, just remove dynamic memory
allocations :
- Structure is 28 bytes on 64bit arches. Using additional 8 bytes
  for holding a pointer seems overkill.
- Two listeners can share same cache line and performance would suffer.

If we really want to save few bytes, we would instead dynamically allocate
whole struct request_sock_queue in the future.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tcp_syn_flood_action() will soon be called with unlocked socket.
In order to avoid SYN flood warning being emitted multiple times,
use xchg().
Extend max_qlen_log and synflood_warned fields in struct listen_sock
to u32
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

These functions do not change the listener socket.
Goal is to make sure tcp_conn_request() is not messing with
listener in a racy way.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Some common IPv4/IPv6 code can be factorized.
Also constify cookie_init_sequence() socket argument.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We'll soon no longer hold listener socket lock, these
functions do not modify the socket in any way.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This method does not touch the listener socket.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

socket no longer needs to be read/write
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

socket is not touched, make it const.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The socket points to the (shared) listener.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Before changing dccp_v6_request_recv_sock() sock argument
to const, we need to get rid of security_sk_classify_flow(),
and it seems doable by reusing inet6_csk_route_req() helper.

We need to add a proto parameter to inet6_csk_route_req(),
not assume it is TCP.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Factorize code to get tcp header from skb. It makes no sense
to duplicate code in callers.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Once we realize tcp_rcv_synsent_state_process() does not use
its 'len' argument and we get rid of it, then it becomes clear
this argument is no longer used in tcp_rcv_state_process()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

None of these functions need to change the socket, make it
const.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Alexander Duyck says:

====================
Minor IPv4 routing cleanups

These patches just contain some minor cleanups to address a few minor
issues.  The first and the third mostly just improve readability.  The
second patch should improve the performance for multicast destination
addresses that do not have a localhost source IP address by avoiding some
unnecessary dereferences.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

err is initialized to -EINVAL when it is declared. It is not reset until
fib_lookup which is well after the 3 users of the martian_source jump. So
resetting err to -EINVAL at martian_source label is not needed.

Removing that line obviates the need for the martian_source_keep_err label
so delete it.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch just swaps the ordering of one of the conditional tests in
ip_route_input_mc.  Specifically it swaps the testing for the source
address to see if it is loopback, and the test to see if we allow a
loopback source address.

The reason for swapping these two tests is because it is much faster to
test if an address is loopback than it is to dereference several pointers
to get at the net structure to see if the use of loopback is allowed.
Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch updates ip_check_mc_rcu so that protocol is passed as a u8
instead of a u16.

The motivation is just to avoid any unneeded type transitions since some
systems will require an instruction to zero extend a u8 field to a u16.
Also it makes it a bit more readable as to the fact that protocol is a u8
so there are no byte ordering changes needed to pass it.
Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

On some embedded systems the EEPROM does not contain a valid MAC address.
In that case it is better to fallback to a generated mac address and
let init scripts fix the value later.
Reported-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
[Changed handcoded setup to use eth_hw_addr_random() and to save new address into HW]
Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

For some reason we were carrying the budget value around between the
various calls to napi->poll.  If for example one of the drivers called had
a bug in which it returned a non-zero value for work this could result in
the budget value becoming negative.

Rather than carry around a value of budget that is 0 or less we can instead
just loop through and pass 0 to each napi->poll call.  If any driver
returns a value for work done that is non-zero then we can report that
driver and continue rather than allowing a bad actor to make the budget
value negative and pass that negative value to napi->poll.

Note, the only actual change here is that instead of letting budget become
negative we are keeping it at 0 regardless of the value returned for work
since it should not be possible for the polling routine to do any actual
work with a budget of 0.  So if the polling routine returns a non-0 value
we are just reporting it and continuing with a budget of 0 rather than
letting that work value be subtracted from the budget of 0.
Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch changes the bridge vlan implementation to use rhashtables
instead of bitmaps. The main motivation behind this change is that we
need extensible per-vlan structures (both per-port and global) so more
advanced features can be introduced and the vlan support can be
extended. I've tried to break this up but the moment net_port_vlans is
changed and the whole API goes away, thus this is a larger patch.
A few short goals of this patch are:
- Extensible per-vlan structs stored in rhashtables and a sorted list
- Keep user-visible behaviour (compressed vlans etc)
- Keep fastpath ingress/egress logic the same (optimizations to come
  later)

Here's a brief list of some of the new features we'd like to introduce:
- per-vlan counters
- vlan ingress/egress mapping
- per-vlan igmp configuration
- vlan priorities
- avoid fdb entries replication (e.g. local fdb scaling issues)

The structure is kept single for both global and per-port entries so to
avoid code duplication where possible and also because we'll soon introduce
"port0 / aka bridge as port" which should simplify things further
(thanks to Vlad for the suggestion!).

Now we have per-vlan global rhashtable (bridge-wide) and per-vlan port
rhashtable, if an entry is added to a port it'll get a pointer to its
global context so it can be quickly accessed later. There's also a
sorted vlan list which is used for stable walks and some user-visible
behaviour such as the vlan ranges, also for error paths.
VLANs are stored in a "vlan group" which currently contains the
rhashtable, sorted vlan list and the number of "real" vlan entries.
A good side-effect of this change is that it resembles how hw keeps
per-vlan data.
One important note after this change is that if a VLAN is being looked up
in the bridge's rhashtable for filtering purposes (or to check if it's an
existing usable entry, not just a global context) then the new helper
br_vlan_should_use() needs to be used if the vlan is found. In case the
lookup is done only with a port's vlan group, then this check can be
skipped.

Things tested so far:
- basic vlan ingress/egress
- pvids
- untagged vlans
- undef CONFIG_BRIDGE_VLAN_FILTERING
- adding/deleting vlans in different scenarios (with/without global ctx,
  while transmitting traffic, in ranges etc)
- loading/removing the module while having/adding/deleting vlans
- extracting bridge vlan information (user ABI), compressed requests
- adding/deleting fdbs on vlans
- bridge mac change, promisc mode
- default pvid change
- kmemleak ON during the whole time
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Gregory CLEMENT says:

====================
net: mvneta: Switch to per-CPU irq and make rxq_def useful

As stated in the first version: "this patchset reworks the Marvell
neta driver in order to really support its per-CPU interrupts, instead
of faking them as SPI, and allow the use of any RX queue instead of
the hardcoded RX queue 0 that we have currently."

Following the review which has been done, Maxime started adding the
CPU hotplug support. I continued his work a few weeks ago and here is
the result.

Since the 1st version the main change is this CPU hotplug support, in
order to validate it I powered up and down the CPUs while performing
iperf. I ran the tests during hours: the kernel didn't crash and the
network interfaces were still usable. Of course it impacted the
performance, but continuously power down and up the CPUs is not
something we usually do.

I also reorganized the series, the 3 first patches should go through
the irq subsystem, whereas the 4 others should go to the network
subsystem.

However, there is a runtime dependency between the two parts. Patch 5
depend on the patch 3 to be able to use the percpu irq.

Thanks,

Gregory

PS: Thanks to Willy who gave me some pointers on how to deal with the
NAPI.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Since the switch to per-CPU interrupts, we lost the ability to set which
CPU was going to receive our RX interrupt, which was now only the CPU on
which the mvneta_open function was run.

We can now assign our queues to their respective CPUs, and make sure only
this CPU is going to handle our traffic.

This also paves the road to be able to change that at runtime, and later on
to support RSS.

[gregory.clement@free-electrons.com]: hardened the CPU hotplug support.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The mvneta driver allows to change the default RX queue trough the rxq_def
kernel parameter.

However, the current code doesn't allow to have any value but 0. It is
actively checked for in the driver's probe because the drivers makes a
number of assumption and takes a number of shortcuts in order to just use
that RX queue.

Remove these limitations in order to be able to specify any available
queue.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Now that our interrupt controller is allowing us to use per-CPU interrupts,
actually use it in the mvneta driver.

This involves obviously reworking the driver to have a CPU-local NAPI
structure, and report for incoming packet using that structure.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The CPU_MAP register is duplicated for each CPUs at different addresses,
each instance being at a different address.

However, the code so far was using CONFIG_NR_CPUS to initialise the CPU_MAP
registers for each registers, while the SoCs embed at most 4 CPUs.

This is especially an issue with multi_v7_defconfig, where CONFIG_NR_CPUS
is currently set to 16, resulting in writes to registers that are not
CPU_MAP.

Fixes: c5aff182 ("net: mvneta: driver for Marvell Armada 370/XP network unit")
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: <stable@vger.kernel.org> # v3.8+
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The MPIC driver currently has a list of interrupts to handle as per-cpu.

Since the timer, fabric and neta interrupts were the only per-cpu
interrupts in the system, we can now remove the switch and just check for
the hardware irq number to determine whether a given interrupt is per-cpu
or not.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Some drivers might use the per-cpu interrupts and still might be built as a
module. Export request_percpu_irq an free_percpu_irq to these user, which
also make it consistent with enable/disable_percpu_irq that were exported.
Reported-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The documentation of request_percpu_irq is confusing and suggest that the
interrupt is not enabled at all, while it is actually enabled on the local
CPU.

Clarify that.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Noticed that the compiler (gcc version 4.8.5 20150623 (Red Hat 4.8.5-4) (GCC))
generated suboptimal assembler code in eth_get_headlen().

This early return coding style is usually not an issue, on super scalar CPUs,
but the compiler choose to put the return statement after this very unlikely
branch, thus creating larger jump down to the likely code path.

Performance wise, I could measure slightly less L1-icache-load-misses
and less branch-misses, and an improvement of 1 nanosec with an IP-forwarding
use-case with 257 bytes packets with ixgbe (CPU i7-4790K @ 4.00GHz).
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Application limited streams such as thin streams, that transmit small
amounts of payload in relatively few packets per RTT, can be prevented
from growing the CWND when in congestion avoidance. This leads to
increased sojourn times for data segments in streams that often transmit
time-dependent data.

Currently, a connection is considered CWND limited only after having
successfully transmitted at least one packet with new data, while at the
same time failing to transmit some unsent data from the output queue
because the CWND is full. Applications that produce small amounts of
data may be left in a state where it is never considered to be CWND
limited, because all unsent data is successfully transmitted each time
an incoming ACK opens up for more data to be transmitted in the send
window.

Fix by always testing whether the CWND is fully used after successful
packet transmissions, such that a connection is considered CWND limited
whenever the CWND has been filled. This is the correct behavior as
specified in RFC2861 (section 3.1).

Cc: Andreas Petlund <apetlund@simula.no>
Cc: Carsten Griwodz <griff@simula.no>
Cc: Jonas Markussen <jonassm@ifi.uio.no>
Cc: Kenneth Klette Jonassen <kennetkl@ifi.uio.no>
Cc: Mads Johannessen <madsjoh@ifi.uio.no>
Signed-off-by: Bendik Rønning Opstad <bro.devel+kernel@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Tested-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Tested-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Adds support for ethtool get time stamp ioctl, which is used by
tcpdump to get the supported time stamp types

eg: tcpdump -i eth5 -J
Time stamp types for eth5 (use option -j to set):
  host (Host)
  adapter_unsynced (Adapter, not synced with system time)

Adds support for adapter unsynced mode, by adding SIOCSHWTSTAMP support
in driver.
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch fixes the compilation error with arm allmodconfig, this error
generated due to unavailability of readq() on 32-bit platform which was
found during net-next daily compilation. In the same time, fix all the
hns drivers compilation warnings.
Signed-off-by: huangdaode <huangdaode@hisilicon.com>
Signed-off-by: zhaungyuzeng <Yisen.zhuang@huawei.com>
Signed-off-by: kenneth Lee <liguozhu@hisilicon.com>
Signed-off-by: yankejian <yankejian@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Convert pxaficp_ir to dmaengine. As pxa architecture is shifting from
raw DMA registers access to pxa_dma dmaengine driver, convert this
driver to dmaengine.
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Tested-by: Petr Cvek <petr.cvek@tul.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>

Convert the pxa IRDA driver to readl and writel primitives, and remove
another set of direct registers access. This leaves only the DMA
registers access, which will be dealt with dmaengine conversion.
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Tested-by: Petr Cvek <petr.cvek@tul.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>

Instead of using directly the OS timer through direct register access,
use the standard sched_clock(), which will end up in OSCR reading
anyway.

This is a first step for direct access register removal and machine
specific code removal from this driver.

This commit changes the behavior, as previously the minimum turnaround
time was counted in 76ns steps, while with this patch it is counted in
microsecond steps. The strictly equal formula would have been :
	    while ((sched_clock() - si->last_clk) * 76 < mtt)
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>

There is no need to have FEATURES_NEED_QUIESCE defined as we
can simply use NETIF_F_RXCSUM instead as done in other parts
of the driver.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The oif has already been checked that it is non-zero; the 2 additional
checks on oif within that if (oif) {...} block are redundant.

CC: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

lan78xx_suspend() may return non-zero from lan78xx_write_reg() in some scenario.
Fix to return 0 when lan78xx_suspend() has no error.
Signed-off-by: Woojung Huh <woojung.huh@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Or Gerlitz says:

====================
Mellanox mlx5 driver update

Bunch of changes from the team, while warming engines for the
upcoming SRIOV support.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>